Coordinate Systems / Projections

The Component tab of the Info pane is our primary interface for seeing the coordinate systems assigned to components and to edit those coordinate systems.  

 

In Manifold, the terms "projection" and "coordinate system" are synonyms and are used interchangeably.

 

Projections

Introductory projections topic.

Assign Initial Coordinate System

Manually assign the initial coordinate system when importing from a format that does not specify the coordinate system.

Repair Initial Coordinate System

Repair an incorrectly assigned initial coordinate system. Used when a mistake has been made with the Assign Initial Coordinate System command or when importing data from a format that specifies the initial coordinate system but which specifies the wrong coordinate system.

Reproject Component

Routine command to re-project data from one coordinate system into a different coordinate system.  

Sub-pixel Reprojection

The direct sub-pixel reprojection option appears in the Method box of the Reproject Component dialog for images.  It enables computation of coordinate system transformations for images to conversion accuracy even more detailed than the size of a single pixel, producing better quality reprojected images than the standard method used by default to reproject images.

Map Projection

How projections for maps are specified.  Maps can have a different projection than the native projection of the layers they include.

Coordinate System

A synonym for projection.  Coordinate systems are an organized way to use numbers to specify locations.

Coordinate System Metrics

A dialog allowing editing of units, unit scale and factors such as local scales and local offsets.

Unit Converter

A dialog providing quick conversion between units and values used in coordinate system parameter boxes.

Base Coordinate System

A sub-dialog of the Coordinate System dialog used to specify what is often called the ellipsoid or datum.

Favorite Base Coordinate Systems

Saved favorite base coordinate systems.  Provides a one-click, simplified way of specifying a frequently used base coordinate system.

Favorite Coordinate Systems

Saved favorite coordinate systems.   Provides a one-click, simplified way of specifying a frequently used coordinate system.

 

 

 To convert a coordinate system into a different coordinate system Manifold can use enhanced accuracy transformation methods that use grid files, including NADCON 5, NADCON (including HARN and HPGN), and NTv2 transformations.  See the Enhanced Accuracy topic in the Quick Start Guide to learn how to use enhanced accuracy transformation methods.

See Also

Example: Assign Initial Coordinate System - Use the Component tab of the Info pane to manually assign an initial coordinate system when importing from a format that does not specify the coordinate system.

 

Example: Change Projection of an Image - Use the Reproject Component command to change the projection of an image, raster data showing terrain elevations in a region of Florida, from Latitude / Longitude to Orthographic centered on Florida.

 

SQL Example: List Transformation Grids - In this example we use a few snippets of easy SQL to list NTv2 and NADCON transformation grids that are available within the grids.dat compressed collection of transformation grid files.   Grid transformation files can be used when creating custom base coordinate systems, for NADCON / HARN / HPGN and NTv2 high accuracy transformations that use grid files.